PCT AG-IP 10.066 What is a “written opinion”?

10.066. What is a “written opinion”? A “written opinion” is a notification, issued by the International Preliminary Examining Authority to the applicant, which indicates any comments by the Authority on the matters mentioned in paragraph 10.064. The written opinion must fully state the reasons for it, must invite the applicant to submit a written reply and must fix a time limit for the reply (usually two months, but extendible at the applicant’s request – for more details, see Rule 66.2(d)). There may be no written opinion if the Authority has no such comments to make (in which case the Authority will proceed directly to the issuance of the international preliminary report on patentability (Chapter II of the PCT)). The Authority may issue one or more additional written opinions if time permits, particularly if the applicant makes a prompt and serious attempt to address the Authority’s comments by argument or amendment.